Abstract
Purpose: :
Ciliochoroidal effusion has been found to commonly develop after panretinal photocoagulation (PRP). This can potentially lead to angle closure . The goal of this study was to quantify immediate postoperative changes in the anterior chamber angle and anterior chamber depth (ACD) after PRP utilizing a Cirrus HD-OCT in patients being treated for diabetic retinopathy in a Bronx population.
Methods: :
This is a prospective study of 23 eyes of patients with diabetic retinopthy necessitating PRP in a tertiary referral practice in the Bronx, NY. Twenty three eyes undergoing PRP were imaged utilizing a 5-line raster anterior segment OCT protocol, 10-15 minutes after instillation of one drop each of tropicamide, cyclogyl, and phenylephrine. The scans were performed by a single skilled operator, and were aligned to the superotemporal quadrant of the operative eye (approximately 11 o’clock OD; 1 o’clock OS). Argon PRP was performed by one attending physician. The treated eye was then re-imaged. ACD was calculated utilzing the Cirrus HD-OCT measuring tool on the post-treatment scan. ACD was similarly calculated on the pre-treated images. Additionally, the anterior chamber angle was manually quantified utilizing the following technique: hard copies of the OCT scans were obtained, and a line was drawn extending from the anterior iris surface towards the anatomic angle. A second line was similarly drawn extending from the corneal endothelium. The angle subtended by the intersection of these two lines was measured, which served as an approximation of the anterior chamber angle in degrees. Statistical analysis was conducted to detect a difference between pre- and post-treated eyes for both ACD and angle measurement
Results: :
Mean ACD before laser was 537.0 um and 528.8 um after laser. Paired t-test showed no statistically significant difference in ACD pre- and post-laser (P>1.5). Mean angle measurement was 38.7 degrees before and 39.8 degrees after LPI, also showing no statistically significant difference before and after LPI (P>1.5).
Conclusions: :
This finding of no statistically significant change in the anteior chamber angle and ACD suggests that PRP may be done on patients without the risk of their angles narrowing.
Keywords: laser • choroid